Sigourney Weaver confirms her return for Avatar 4 and Avatar 5 before the release of Avatar: Fire and Ashbiological daughter of Grace's avatar.

Per Deadline, Weaver confirms that she will be a part of Avatar 4 and Avatar 5. When asked directly if she would "be present in Avatar four and five," Weaver confirmed by saying "Yes, I think I am allowed to say that." In addition to confirming her appearance in the later sequels, Weaver reflected on "reading the script of the first Avatar" and not being able to "imagine any of it being shot." She noted that she "just finished working on Avatar 3 earlier this month" and that Avatar 4 and 5 are "written."

WEAVER: I reading the script of the first Avatar and reading about these blue people with pointed ears and tails riding on these creatures through floating mountains … I couldn’t imagine any of it being shot. I honestly couldn’t imagine how he would ever make a film that looked like this and had these elements. But I’m so glad for Jim, and for the success of these films, which has meant we’re able to keep making them. I just finished working on Avatar 3 earlier this month, actually, and I think the series will continue to grow and be more and more hard-hitting…

DEADLINE: So you haven’t started working on four and five yet?

WEAVER: They’re written. We know what they are. They’re really good. But Jim is still finishing three. It’s nice to look forward to them.

DEADLINE: And you’ll be present in Avatar four and five, we assume?

WEAVER: Yes, I think I’m allowed to say that.

Why Weaver's Appearance in Avatar 4 and 5 Is So Exciting

Kiri Is An Essential Part Of Avatar

It is exciting to hear Weaver talk about her appearance in Avatar 4 and Avatar 5, for Kiri is one of the most fascinating elements of the series. One function Kiri has is to expand the lore of the Avatar universe, as she is the first known incarnation of a child being made from the cells of a dead person's avatar. The mystery around Kiri could be employed in other parts of the series and could be used for good or bad in future movies.

There are moments in the sequel wherein Kiri appears to be feeling this heightened power, but these abilities are not fully explained in Avatar: The Way of Water.

Kiri helps add to the theme of unconventional families that is encapsulated by the Sully family in Avatar: The Way of Water. Prior to Neteyam's death, Jake and Neytiri essentially have five children — biological children, Neteyam, Lo'ak, and Tuk, adopted daughter Kiri, and Spider, who acts as almost their honorary son despite being a human child. The presentation of this unlikely family hints at themes of unconventional family structures, which will likely become increasingly vital to the franchise as the Sully family is explored in more detail.

There is still a lot more growing that Kiri can do as a character herself, making her longevity in the Avatar franchise a logical step. Throughout Avatar: The Way of Water, it is suggested that Kiri has a deep connection with the Na'vi god, Eywa. There are moments in the sequel wherein Kiri appears to be feeling this heightened power, but these abilities are not fully explained in Avatar: The Way of Water. Avatar: Fire and Ash, Avatar 4, and Avatar 5 can dedicate energy to this part of Kiri's character, making Weaver's confirmed return exciting.

Source: Deadline